Glacier Landforms: Moraines

Moraines are accumulations of dirt and rocks that have fallen onto the glacier surface or have been pushed along by the glacier as it moves. The dirt and rocks composing moraines can range in size from powdery silt to large rocks and boulders. A receding glacier can leave behind moraines that are visible long after the glacier retreats.

An eroded moraine juts above the landscape in the Rhone Valley, Switzerland. Giant boulders stud some of the pinnacles, left behind by a retreating glacier. A small tunnel has been cut through the moraine, seen on the left side of the photograph. —Credit: Photograph by Harry Fielding Reid. 1902. From the Glacier Photograph Collection. Boulder, Colorado USA: National Snow and Ice Data Center. Digital media.

This ground-view of a moraine shows the immense amount of rock and debris that a glacier plows in front of it or pushes off to the side. —Credit: Tim Bocek

The terrain in this photograph is covered with piles of debris—an extensive moraine left behind by a retreating glacier. —Credit: Carol Mitchell